Picture frame



p 1957 G. D. BOYD 2,806,310

PICTURE FRAME Filed July 19, 1954 GORDON 507D INVENTORQ PICTURE FRAME Gordon D. Boyd, Oak Park, Iii.

Application July 19, 1954, Serial No. 444,320

2 Claims. (Cl. 40-154) This invention relates to a picture frame, and, more particularly, to a picture frame constructed from corrugated paperboard.

Most of the picture frames used in the past have been constructed of wood of various types. As a consequence, frames of this nature were relatively heavy, and, more importantly, expensive because of the craftsmanship involved. My invention overcomes these two disadvantages by using paperboard for the material from which the frame is constructed.

The paperboard picture frames previously known to the art have been subject to the drawback of warping extensively with changes in humidity. I have found that the warpage in paperboard frames is more pronounced than that occurring in wood frames. To overcome this drawback, I have devised a material for coating paperboard frames which is relatively impervious to moisture and which will not crack or otherwise become unsightly upon standing for a considerable period of time. It is to be noted that this characteristic is important in a coating for a frame since a frame for a picture is usually intended to be used for a great number of years.

In addition, the coating applied to the paperboard frame of my invention lends itself to being molded after application but before drying into an eye-pleasing and artistic surface. Thus, the grain and texture of wooden frames can be simulated, if so desired.

Since paperboard is produced in only a relatively small thickness, it is necessary to form the paperboard into a tubular member to give the the frame substantial thickness, which also gives the frame an eye-pleasing appearance. The provision of an outwardly sloping frame whereby an impression of depth is created is especially desirable. To achieve this end I have found corrugated paperboard particularly suitable since it can be folded partially on itself without cracking both outer surfaces.

It is therefore an object of my invention to provide a relatively light-Weight and inexpensive picture frame. Another object is to provide a picture frame constructed of corrugated paperboard. Still another object is to provide a frame in which corrugated paperboard is coated with a moisture impervious material to prevent substantial warping of the paperboard. Other objects and advantages will be seen as the specification proceeds.

Essentially, my invention includes a picture frame constructed of corrugated paperboard folded successively on itself to form a frame characterized by tubular sides. The frame is coated with a moisture impervious material.

An embodiment of my invention will be described in conjunction with the accompanying drawing, in which: Fig. 1 is a perspective view of a picture frame made according to the teaching of my invention; Fig. 2 is a cross-sectional view taken along the line 2-2 of Fig. 1; and Fig. 3 is an elevational view of an articulated die-cut, laminated, corrugated paperboard sheet useful in constructing an integral picture frame.

Referring to the drawing and, in particular, Fig. 1, a picture frame made according to the teaching of my inice vention is generally designated 10. Picture frame 10 includes four side pieces 11, end-joined to form a substantially rectangular, open-centered structure. The preferred embodiment shown is constructed with sides having beveled ends, the bevel being at an angle of 45 so as to permit the formation of a miter joint 12. A miter joint is formed when two pieces of identical cross section are joined at their ends, and where the joined ends are beveled at equal angles. Frame 10 is shown as rectangular in elevation, but it may be square or even possess a greater number of sides, in which case the joined ends are of slightly less taper.

It is to be noted that the frame has substantial depth, as can be better seen by referring to Fig. 2 which shows the frame of Fig. 1 in cross-section. Depth is provided in the frame by forming each side piece 11 according to the following procedure: one surface of a sheet of corrugated paperboard is provided with a series of scorings 13 corresponding to folds 13a. I have found that the possibility of warpage is further substantially decreased if the folds are made against the grain of the corrugated paperboard sheet, or, in other words, perpendicular to the length of the flutes making up the corrugated portion of the sheet. The sheet is then folded partially on itself as by folding it inwardly and upwardly to form face surface 14; then downwardly and outwardly to form end surface 15; then downwardly to form rear surface 16 which is secured to the unfolded portion 17 of the sheet. In the preferred embodiment, the downwardly folded portion, constituting rear surface 16, is of such a width as to cooperate with unfolded portion 17 to produce inset portion 18. Inset portion 18 is an especially useful aid in mounting a picture such as is shown at 19. It is not essential to forming the aforementioned inset portion 18 that rear surface 1'6 be narrower than unfolded portion 17, only that fold 16a be made at such position with respect to the width of the sheet as to provide inset portion 18. In this connection, I should like to point out that by making the folds as shown in Fig. 2 a stronger frame is produced.

It is to be clearly understood that the procedure outlined above is only one way in which tubular side pieces 11 can be formed. For example, the folding procedure can be reversed and an identical side piece produced. Many variations are possible such as having an inwardly sloping face surface 14 rather than the outwardly sloping form pictured. Still further, by making an additional fold, the triangular cross-section form of side piece may be made into a rectangular or square form. An obvious modification of the type of frame shown in Fig. 2 would be to use surface 16 as the face surface of the frame rather than the rear surface, thereby off-setting the picture from the wall on which it is hung.

After the side pieces 11 have been formed in the man-' ner set forth above and provided with beveled ends, they are assembled into the rectangular type structure shown in Fig. 1. I have found a convenient way of securing the respective side members together to consist of using relatively inexpensive gummed paper or tape.

After the frame is assembled and secured together as outlined above, a coating is applied to prevent the frame from warping under changes in moisture conditions in the atmosphere surrounding it. I have found a suitable coating for this purpose to consist of liquid latex, which is the primary ingredient of rubber and is soluble in water. Liquid latex alone has proved unsatisfactory as a coating inasmuch as it does not adhere to the frame after drying. Therefore, I have found it necessary to supplement the liquid latex with some kind of binder material adapted to give the latex adherent qualities. However, other rubber-like substances may be equally useful so I do not limit my invention to the use of latex.

Many materials are suitable to impart to latex the desirable adherent quality mentioned above. Since, however, I have found that water is the most economical solvent for latex, I prefer to use as the binder-additive a material which is also water soluble. It will be immediately apparent to those skilled in the art that the particular binder to be added to latex to render ,it adhesive is a matter of choice. I have also found most proportions of latex and'the binder suitable as moisture impervious coatings. It will immediately be recognized that the proportions of the two ingredients have to be adjusted so as not to deprive the coating either of its elastic property, as would result from lessening too much the proportion of latex, or deprive the coating of its ad-. herent property, by decreasing too much the proportion of the binder. Among the many materials useful as binder-additives, I have found especially suitable casein paint and a commercial construction material manufactured by the United States Gypsum Company known as Marblecoat. Of the foregoing, I prefer casein paint.

Upon application of the coating as specified above, the frame is permitted to dry, after which the coating forms an adherent moisture-impervious layer. Drying ordinarily. requires two to four hours. Prior to drying, the coating can be molded or shaped into various artistic and eye-pleasing surfaces such as contours, grooves and the like. After drying, the coating is adapted to be covered with a layer of paint if desired.

It is not necessary that the frame of my invention be assembled from four separate side pieces, but instead may be made from a single sheet of corrugated paperboard. However, a much larger sheet is required inasmuch as the central portion is cut out, which increases the cost of the material going into the frame. In the event such an integral frame is desired, it can be produced from a single sheet diecut similar to that shown in an articulated form in Fig. 3. It is to be noted, however, that Warpage is likely to occur in the side pieces which are folded parallel with the corrugations as contrasted with the preferred embodiment wherein they are folded perpendicular to the corrugations. This tendency toward warpage can be minimized by laminating an additional ply of corrugated paperboard with the corrugations of the second ply running perpendicular to those of the first. When the single sheet procedure is employed, a central cut-out 20 is provided of dimensions suitable for framing the picture which is to be mounted behind the frame. To provide the side pieces 11, corner cut-outs 21 are made which permit the intermediate flap portions 22 provided to be folded along dotted lines 23 so as to form tubular side pieces 11 such as are shown in Fig. 2. When flap portions 22 are folded along dotted lines 23, folded surface 24 corresponds to end surface 15 of Pig. 2, surface 25 corresponds to face surface 14 of Fig. 2, and edge 26 corresponds to unfolded portion 17. The particular form of zig-zag corner cutout 21 can be readily determined once the slope of the various surfaces is decided.

I have not described in detail the application of the coating to the picture frame inasmuch as the coating described is adapted to be applied in many ways. It is preferred, however, to coat the entire frame, both front and back, so as to minimize the possibility of warpage. Further, a thicker coating may be applied to face surface 2,806,310 V y I y 4 14 so that grooved surface 27 may be molded into the coating after application but prior to complete evaporation of the solvent therefrom.

In this respect it is to be noted that the binder ingredient of the coating also serves as a filler for the rubber-like ingredient, giving the ultimate coating a body not achieved by the rubber-like material alone. This characteristic is important in rendering the coating moldable since I have found, for example, that a /2 layer of latex solution contracts upon drying to about Ms" thick layer.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be inferred therefrom as modifications will be obvious to those skilled in the art.

I claim:

1. A picture frame comprising four corrugated paperboard side portions, said side portions being connected at their ends to form a substantially rectangular frame wherein the ends of said side portions provide substantial abutting'areas at the connections, means securing together the connected ends of said side portions, the entire frame being coated with a moisture impervious material adapted to be molded into an artistic surface, each of said side portions having been previously formed into a tubular member from a single sheet of corrugated paperboard by folding said shect partially on itself along at least three spaced parallel longitudinal lines and securing the edges of said sheet together in overlapping relation.

2. A picture frame comprising four tubular corrugated paperboard sides, each side having beveled ends, a beveled end of each side being joined to a beveled end of another side to form a four-sided frame structure characterized by miter joints, said joints providing substantial abutting areas for adjacent sides to firmly connect the same; the entire frame structure beingcoated with a moldable moisture-impervious coating comprising latex and a casein paint whereby Warping of said frame structure particularly in the abutting areas of said joints, is substantially prevented, each of said sides having previously been formed from a single sheet of corrugated paperboard by partially folding said sheet on itself along three spaced parallel lines, said lines being longitudinal of the sheet and perpendicular to the corrugations thereof, and by securing together the longitudinal edge folds of said sheet in partial overlapping relation, the outer edges of the overlying secured longitudinal fold being spaced from the folded edge of the underlying secured longitudinal fold to provide an inset portion adapted to receive a picture.

References Cited in the file of this patent UNITED STATES PATENTS 1,223,409 McMillan Apr. 24, 1917 2,250,491 Lurrain July 29, 1941 2,395,369 Burr Feb. 19, 1946 2,458,349 Cross Jan. 4, 1949 2,613,467 'Borglin Oct. 14, 1952 FOREIGN PATENTS 906,898 France Feb. 22, 1946 a A M-t 

